Noise predictions for shear layers

Abstract

This chapter contributes to the investigation of acoustic noise generation in shear layers with the use of advantages of parallel computing. Both noise propagation and generation are simulated by the linear acoustic equations with source terms which are derived, in its turn, on the base of complete Navier-Stokes equations system and triple flow decomposition. The difficulty in numerical prediction of aeroacoustics problems results in particular from a small scale of acoustic pulsation, especially in comparison with large scale oscillations of gasdynamic parameters. This small scale places strict constrains on the numerical algorithms in use and requires powerful computer facilities due to the need of using higly refined computational meshes for resolving such small scale acoustic disturbances. In particular, to resolve high frequency perturbations under the requirement of 10 nodes per wave, it is necessary to use huge computational meshes.